If you want to use the WordPress OneClick feature, i have some news for you:

"file ownership: all of your WordPress files must be owned by the user under which your web server executes. In other words, the owner of your WordPress files must match the user under which your web server executes. The web server user (named "apache", "web", "www", "nobody", or some such) is not necessarily the owner of your WordPress files. Typically, WordPress files are owned by the ftp user which uploaded the original files. If there is no match between the owner of your WordPress files and the user under which your web server executes, you will receive a dialog box asking for "connection information", and you will find that no matter what you enter in that dialog box, you won't be able to update using the "Update Now" button."
http://codex.wordpress.org/Updating_WordPress#Automatic_Update.
Date: 3/31/2014

Proposition #1

So technically whatever permissions you painstakingly set up on your WordPress folder, you have to scratch them and run something like :
chown apache:apache * -R on your wordpress folder.

Wow that is crazy! what about my sftp accounts?

Proposition #2

Another solution will be to switch your web server to the user account that owns the WordPress core files temporarily, then run the OneClick update then replace the user back after you are done.

I do not like either solutions, but i will keep on looking for a better way to handle that in the meantime if you have a comment please express yourself.

If you do not have anything too confidential, you would probably want all your developers to have have 775 and 664 permission by default on all folders and files respectively. They will be able to change each other’s files without a big deal, granted you are dealing of course with responsible developers.

FTP

Here is the way to do it with ftp (vsftp). Don’t forget to restart your ftp server and your ftp client.
Modify your vsftp.conf to include the following:

local_umask=0002
file_open_mode=0777

and

SFTP

Here is the way to do in in sftp

Follow the instructions in this website below:
http://john.parnefjord.se/node/62/print

NOTE: This post assumes that you are working on a development server. For live servers, it is recommended that only a single user account has write access.